virtualbox.org

Here's my setup. Help https://imgur.com/a/1qpMcs3

Provide a VM log file. Make sure the VM is fully shut down, then right click it in the manager UI. Select "Show Log" and save "VBox.log" (no other file) to a zip file. Attach the zip here.

p.s. IMG tags do not work with offsite images. Images should be attached directly here, if needed. In this case the image is not needed, since a static screenshot of the manager is not very useful.

Also read HMR3Init: Attempting fall back to NEM (Hyper-V is active).

Thanks for replying. Here's the log.

Reduce guest cores to 2. Leaving VirtualBox (the app running on the host) with 0 cores will not lead to it working well.

But your real problem is that Hyper-v is enabled.

00:00:02.459181 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
00:00:02.483401 NEM: info: Found optional import WinHvPlatform.dll!WHvQueryGpaRangeDirtyBitmap.
00:00:02.483461 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work...

See HMR3Init: Attempting fall back to NEM (Hyper-V is active).

Thanks, 2 or 3 cores for the guest OS is fine, 4 or more and it won't boot. Don't really see the point here. I have another question, why is Nested VT-x/AMD-V is not available?

If you had read the message from your log about fall back to NEM and the reference you were given about it you would already have a pretty good idea.

hgajshb wrote:Thanks, 2 or 3 cores for the guest OS is fine, 4 or more and it won't boot.

I said 2 cores, I did not say "or 3 or 4".

hgajshb wrote:why is Nested VT-x/AMD-V is not available?

You have Hyper-v running, therefore Hyper-v owns VT-x. VirtualBox can hardly pass through a feature it can't access.

I have turned hyper-v off and it is still not available.

You followed the instructions in the linked FAQ? Then please provide a new zipped log which shows that.

Note that turning off Hyper-v in Windows "Optional Features" dialog does not do anything useful, which is why the FAQ tells you not to bother doing that.